PLECOPTEBA OF XOBTH AMEBICA 271 



polished ; clypeus quite rugose. The ocelli form an almost 

 equilateral triangle whose base is a little longer than the 

 sides; hind ocelli about twice as close to eyes as to each 

 other. Antennae black, submonilif orm ; third segment a 

 little longer than second; fourth equals second in length. 

 Palpi black, short. 



Prothorax black, narrower than head, wider than long, 

 narrowed behind ; sides convex in front and middle, front 

 angles very broadly rounded, hind angles narrowly 

 rounded; surface coarsely rugose and hairy. Meso- and 

 metathorax black, hairy. Legs brown or blackish. In the 

 specimens with lighter legs the femora are darker 

 towards the tips. First and third tarsal segments sub- 

 equal; second segment short, not more than one-fourth 

 as long as first. Wings uniformly and lightly infuscated, 

 veins dark brown, several crossveins between Rl and R2 

 beyond. the cord in both fore and hind wings. Venation 

 as in plate 47, figure 7. 



Abdomen blackish brown, somewhat lighter towards 

 the tip, covered with rather long hair, the tip of the ab- 

 domen being especially hairy. Cerci or tails submonili- 

 form, dark brown, very hairy, the hairs longer than the 

 basal segments, which are about as long as wide ; beyond 

 the middle the segments are three to four times as long 

 as wide. 



Male, unknown. 



Female. The eighth abdominal sternite truncate and not 

 noticably produced. 



Distribution. — Four "females, including type 11364, from 

 Pullman, Wash., April 9, 1897 (Banks Collection, Museum 

 of Comparative Zoology, Cambridge, Mass.) ; one female, 

 Pullman, Wash., March 16, 1909 (W. M. Mann) . 



Genus CAPNELLA Claassen. 



1924. Capnella Claassen, Can. Ent., 56:43. 



Small blackish species, mostly under 10 mm. in length ; 

 usually winged, the males often short-winged and in 

 at least one species the males are wingless. 



Head blackish, wider than prothorax; ocelli three, the 

 hind ocelli closer to the eyes than to each other. An- 

 tennae blackish, long. 



Prothorax usually a little wider than long; angles 

 rounded ; surface slightly to moderately rugose. Legs 

 nearly uniformly brown or blackish ; middle tarsal seg- 

 ment very short ; first and third tarsal segments subequal. 

 Wings subhyaline, with heavy irregular venation, the 



